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Decreased levels of cerebrospinal fluid (CSF) Abeta42 is a diagnostic marker of Alzheimer's disease. To clarify the biological basis of this marker, the physiological alterations of CSF Abeta40 and Abeta42 by aging were studied. CSF samples from 92 normal subjects between 8 and 89 years old were measured using a specific ELISA for Abeta40 and Abeta42(43). High concentrations of Abeta40 and Abeta42(43) in the young group, under 29 years old, changed to be at low concentrations in the adult group between 30 and 59 years old. Subsequently, the levels increased again with age. Third order regression analysis showed a significant correlation between the levels of Abeta40 and age (Y = - 169 X(3) + 3.1X(2)- 0.02X + 4135; P < 0.034) and between the levels of Abeta42(43) and age (Y = - 46 X(3) + 0.9 X(2)- 0.005X + 992; P < 0.005). The levels of CSF Abeta40 and Abeta42(43) were physiologically regulated to show a U-shaped natural course in normal aging. These findings suggested that the physiological increase of Abeta42(43) over 59 years of age is selectively inhibited in Alzheimer's disease.  相似文献   
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Few studies have investigated the relation between glucose tolerance status and ultrasonographically determined gallstone disease. Using a 75-g oral glucose tolerance test, we examined the association of impaired glucose tolerance (IGT) and non-insulin-dependent diabetes mellitus (NIDDM) with gallstone disease in Japanese men. Subjects were men aged 48 to 59 of the Japan Self-Defense Forces who received a preretirement health examination between October 1986 to December 1994. After exclusion of 12 men under insulin treatment in the consecutive series of 7637 men, 174 were found to have gallstones; 103 were at the state of postcholecystectomy, and 6899 had normal gallbladder. IGT and NIDDM were associated with a modestly increased risk of gallstone disease; adjusted odds ratios were 1.3 (95% confidence interval [CI]: 0.9–1.8) for IGT and 1.3 (95% CI: 0.8–2.0) for NIDDM after adjustment for hospital, rank, smoking, alcohol use, and body mass index. Adjusted odds ratio for IGT and NIDDM combined was 1.3 (95% CI: 1.0–1.7, p=0.08). When prevalent gallstones and postcholecystectomy were considered separately, NIDDM showed a significant, positive association with postcholecystectomy, but not with prevalent gallstones. The findings add to evidence that glucose intolerance is associated with a modest increase in the risk of gallstone disease.  相似文献   
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BACKGROUND: Endoscopic mucosal resection is an established treatment option for early stage gastric cancer. However, several problems with endoscopic mucosal resection remain to be solved, such as appropriate treatment for recurrence and incomplete tumor resection. The outcome for patients undergoing endoscopic aspiration mucosectomy (endoscopic mucosal resection) by a modification of the cap-fitted technique was evaluated retrospectively to determine factors associated with complete resection and tumor recurrence. METHODS: Endoscopic mucosal resection was performed in 106 patients with early stage gastric cancers up to 20 mm in diameter that were well or moderately differentiated adenocarcinoma. All were superficial lesions without ulceration, distinct signs of submucosal invasion, or a poorly demarcated border. En bloc (tumors <10 mm in diameter) or piecemeal (tumors 10-20 mm in diameter) resection was performed. Follow-up endoscopy was performed at 2, 6, 12, 18, and 24 months and thereafter once per year. Outcome and factors associated with complete resection and tumor recurrence were assessed retrospectively. RESULTS: Sixty-eight patients (64%) underwent en bloc resection and 38 (36%) piecemeal resection. The mean longest dimension (SD) of the resected lesions was significantly greater after piecemeal resection (12.3 [4.0] mm) than after en bloc resection (7.6 [4.0] mm; p < 0.01). In patients with tumors completely resected, there was no recurrence after either en bloc or piecemeal resection. Six of 8 patients found to have submucosal invasion after endoscopic mucosal resection underwent surgery. Patients with incompletely resected intramucosal lesions underwent additional endoscopic treatment. Cancer recurred in 3 patients (2.8%), all of whom had lesions measuring more than 15 mm in diameter. CONCLUSIONS: Endoscopic mucosal resection is safe and useful for the management of early stage gastric cancer. Further improvement in outcome requires more accurate preoperative diagnosis and postoperative histopathologic evaluation. Patients with incompletely resected lesions should undergo aggressive additional treatment.  相似文献   
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The L/N-type calcium channel blocker cilnidipine has been shown to suppress aldosterone production induced by angiotensin II (Ang II) in vitro. In addition, cilnidipine also suppresses the reflex tachycardia induced by its antihypertensive action in vivo. We investigated the effects of cilnidipine on the reflex aldosterone production induced by its antihypertensive action, to identify the differences in the effects of cilnidipine from those of the L-type calcium channel blocker nifedipine. Male SHR/Izm rats were anesthetized by intraperitoneal injection of pentobarbital sodium, and administered an intravenous infusion of saline supplemented or not with Ang II for 30 min. Blood pressure was monitored continuously in the femoral artery. Each of the calcium channel blockers under study was administered intravenously as a bolus through the femoral vein 1 min after the start of the Ang II infusion, and blood samples were collected 30 min after the start of the Ang II infusion. Following administration at nonhypotensive doses, all calcium channel blockers tended to decrease the plasma aldosterone. In particular, cilnidipine significantly suppressed the plasma aldosterone levels. On the other hand, under the condition of Ang II-induced hypertension, administration of a hypotensive dosage of cilnidipine showed no effect on the plasma aldosterone levels, whereas a hypotensive dosage of nifedipine significantly increased the plasma aldosterone levels. Our results suggest that the L/N-type calcium channel blocker cilnidipine reduces the plasma aldosterone level by suppressing the aldosterone production induced by reflex upregulation of the renin-angiotensin-aldosterone system associated with reduction of the blood pressure.  相似文献   
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